Frequency-Amplitude Ratio of Ocular Vestibular-Evoked Myogenic Potentials for Detecting Meniere's Disease: A Preliminary Investigation.

Objective: Several parameters of ocular vestibular-evoked myogenic potential (oVEMP) have been used to identify Meniere's disease. Nonetheless frequency-amplitude ratio (FAR), which is the ratio of amplitude between two frequencies, is one among the parameters that has failed to attract researchers' attention despite proving its worth in diagnosis of Meniere's disease when used in conjunction with cervical VEMP. Thus, the present study aimed at investigating the utility of FAR of oVEMP in identifying Meniere's disease and finding out an optimum frequency pair for its diagnosis. Design: Using a case-control design, oVEMPs were recorded for tone bursts of 500, 750, 1000, and 1500 Hz from 36 individuals with unilateral definite Meniere's disease in the age range of 15 to 50 years. For comparison purposes, oVEMP at the above frequencies were also obtained from an equal number of age- and gender-matched healthy individuals. The amplitudes of 750, 1000, 1500 Hz and tuned frequency, which was the frequency with the largest peak to peak amplitude among the above-mentioned frequencies, were divided by the amplitude of 500 Hz to obtain FARs for 750/500, 1000/500, 1500/500, and tuned frequency/500 frequency pairs. Results: The results revealed significantly higher FAR in the Meniere's disease group than the healthy controls for all the frequency pairs (p

from #Audiology via ola Kala on Inoreader http://ift.tt/1ZMjaqX
via IFTTT

Frequency-Amplitude Ratio of Ocular Vestibular-Evoked Myogenic Potentials for Detecting Meniere's Disease: A Preliminary Investigation.

Objective: Several parameters of ocular vestibular-evoked myogenic potential (oVEMP) have been used to identify Meniere's disease. Nonetheless frequency-amplitude ratio (FAR), which is the ratio of amplitude between two frequencies, is one among the parameters that has failed to attract researchers' attention despite proving its worth in diagnosis of Meniere's disease when used in conjunction with cervical VEMP. Thus, the present study aimed at investigating the utility of FAR of oVEMP in identifying Meniere's disease and finding out an optimum frequency pair for its diagnosis. Design: Using a case-control design, oVEMPs were recorded for tone bursts of 500, 750, 1000, and 1500 Hz from 36 individuals with unilateral definite Meniere's disease in the age range of 15 to 50 years. For comparison purposes, oVEMP at the above frequencies were also obtained from an equal number of age- and gender-matched healthy individuals. The amplitudes of 750, 1000, 1500 Hz and tuned frequency, which was the frequency with the largest peak to peak amplitude among the above-mentioned frequencies, were divided by the amplitude of 500 Hz to obtain FARs for 750/500, 1000/500, 1500/500, and tuned frequency/500 frequency pairs. Results: The results revealed significantly higher FAR in the Meniere's disease group than the healthy controls for all the frequency pairs (p

from #Audiology via ola Kala on Inoreader http://ift.tt/1ZMjaqX
via IFTTT

Frequency-Amplitude Ratio of Ocular Vestibular-Evoked Myogenic Potentials for Detecting Meniere's Disease: A Preliminary Investigation.

Objective: Several parameters of ocular vestibular-evoked myogenic potential (oVEMP) have been used to identify Meniere's disease. Nonetheless frequency-amplitude ratio (FAR), which is the ratio of amplitude between two frequencies, is one among the parameters that has failed to attract researchers' attention despite proving its worth in diagnosis of Meniere's disease when used in conjunction with cervical VEMP. Thus, the present study aimed at investigating the utility of FAR of oVEMP in identifying Meniere's disease and finding out an optimum frequency pair for its diagnosis. Design: Using a case-control design, oVEMPs were recorded for tone bursts of 500, 750, 1000, and 1500 Hz from 36 individuals with unilateral definite Meniere's disease in the age range of 15 to 50 years. For comparison purposes, oVEMP at the above frequencies were also obtained from an equal number of age- and gender-matched healthy individuals. The amplitudes of 750, 1000, 1500 Hz and tuned frequency, which was the frequency with the largest peak to peak amplitude among the above-mentioned frequencies, were divided by the amplitude of 500 Hz to obtain FARs for 750/500, 1000/500, 1500/500, and tuned frequency/500 frequency pairs. Results: The results revealed significantly higher FAR in the Meniere's disease group than the healthy controls for all the frequency pairs (p

from #Audiology via xlomafota13 on Inoreader http://ift.tt/1ZMjaqX
via IFTTT

Transmission beam characteristics of a Risso's dolphin (Grampus griseus)

The echolocation system of the Risso's dolphin (Grampus griseus) remains poorly studied compared to other odontocete species. In this study, echolocation signals were recorded from a stationary Risso's dolphin with an array of 16 hydrophones and the two-dimensional beam shape was explored using frequency-dependent amplitude plots. Click source parameters were similar to those already described for this species. Centroid frequency of click signals increased with increasing sound pressure level, while the beamwidth decreased with increasing center frequency. Analysis revealed primarily single-lobed, and occasionally vertically dual-lobed, beam shapes. Overall beam directivity was found to be greater than that of the harbor porpoise, bottlenose dolphin, and a false killer whale. The relationship between frequency content, beam directivity, and head size for this Risso's dolphin deviated from the trend described for other species. These are the first reported measurements of echolocation beam shape and directivity in G. griseus.

from #Audiology via xlomafota13 on Inoreader http://ift.tt/1O33J8B
via IFTTT

In situ measurements of the oblique incidence sound absorption coefficient for finite sized absorbers

Absorption coefficients are mostly measured in reverberation rooms or with impedance tubes. Since these methods are only suitable for measuring the random incidence and the normal incidence absorption coefficient, there exists an increasing need for absorption coefficientmeasurement of finite absorbers at oblique incidence in situ. Due to the edge diffraction effect, oblique incidence methods considering an infinite sample fail to measure the absorption coefficient at large incidence angles of finite samples. This paper aims for the development of a measurement method that accounts for the finiteness of the absorber. A sound field model, which accounts for scattering from the finite absorber edges, assuming plane wave incidence is derived. A significant influence of the finiteness on the radiation impedance and the corresponding absorption coefficient is found. A finite surface method, which combines microphone array measurements over a finite sample with the sound field model in an inverse manner, is proposed. Besides, a temporal subtraction method, a microphone array method, impedance tube measurements, and an equivalent fluid model are used for validation. The finite surface method gives promising agreement with theory, especially at near grazing incidence. Thus, the finite surface method is proposed for further measurements at large incidence angles.

from #Audiology via xlomafota13 on Inoreader http://ift.tt/1O33ISb
via IFTTT

Lateralization of stimuli with alternating interaural time differences: The role of monaural envelope cues

A temporally acute binaural system can help to resolve inherent fluctuations in binaural information that are often present in complex auditory scenes. Using a broadband noise stimulus that rapidly alternates between two different values of interaural time difference(ITD), the ability of the binaural system to hear the lateral position resulting from one of the ITD values was investigated. Results show that listeners are able to accurately lateralize brief noise tokens of only 3–7 ms in duration. In two subsequent experiments, the role of an amplitude modulation (AM) imposed on the ITD-switching stimulus used in the first experiment was tested. For wideband stimuli, the temporal position of the ITD target relative to the phase of the AM did not influence absolute lateralization or detection performance. When the stimuli were narrowband, however, detection of the ITD target was best when temporally positioned in the rising portion of the AM. These experiments illustrate that the auditory system is capable of making accurate lateral estimates of very brief moments of ITD information. Furthermore, for these instantaneous changes in ITD information, the stimulus bandwidth can influence the role of envelope cues for the readout of binaural information.

from #Audiology via xlomafota13 on Inoreader http://ift.tt/1O33H0p
via IFTTT

Mutation update and uncommon phenotypes in a French cohort of 96 patients with WFS1-related disorders.

Related Articles

Mutation update and uncommon phenotypes in a French cohort of 96 patients with WFS1-related disorders.

Clin Genet. 2015 May;87(5):430-9

Authors: Chaussenot A, Rouzier C, Quere M, Plutino M, Ait-El-Mkadem S, Bannwarth S, Barth M, Dollfus H, Charles P, Nicolino M, Chabrol B, Vialettes B, Paquis-Flucklinger V

Abstract
WFS1 mutations are responsible for Wolfram syndrome (WS) characterized by juvenile-onset diabetes mellitus and optic atrophy, and for low-frequency sensorineural hearing loss (LFSNHL). Our aim was to analyze the French cohort of 96 patients with WFS1-related disorders in order (i) to update clinical and molecular data with 37 novel affected individuals, (ii) to describe uncommon phenotypes and, (iii) to precise the frequency of large-scale rearrangements in WFS1. We performed quantitative polymerase chain reaction (PCR) in 13 patients, carrying only one heterozygous variant, to identify large-scale rearrangements in WFS1. Among the 37 novel patients, 15 carried 15 novel deleterious putative mutations, including one large deletion of 17,444 base pairs. The analysis of the cohort revealed unexpected phenotypes including (i) late-onset symptoms in 13.8% of patients with a probable autosomal recessive transmission; (ii) two siblings with recessive optic atrophy without diabetes mellitus and, (iii) six patients from four families with dominantly-inherited deafness and optic atrophy. We highlight the expanding spectrum of WFS1-related disorders and we show that, even if large deletions are rare events, they have to be searched in patients with classical WS carrying only one WFS1 mutation after sequencing.

PMID: 24890733 [PubMed - indexed for MEDLINE]

from #Audiology via xlomafota13 on Inoreader http://ift.tt/1Pd9qyG
via IFTTT

Comparison of temporal and stride characteristics in myotonic dystrophies type 1 and 2 during dual-task walking

Publication date: February 2016
Source:Gait & Posture, Volume 44
Author(s): S. Radovanović, S. Perić, D. Savić-Pavićević, V. Dobričić, J. Pešović, V. Kostić, V. Rakočević-Stojanović
ObjectiveWe analyzed temporal and stride characteristics in patients with myotonic dystrophy type 1 (DM1) and type 2 (DM2) while performing dual mental and motor tasks, and investigated correlations between gait parameters and cognitive impairments.MethodDual-task walking was performed by 37 patients (20 DM1 and 17 DM2) and 48 healthy subjects divided into two groups, age- and gender-matched control group for DM1 (HC1) and age- and gender-matched control group for DM2 (HC2). The subjects performed a basic walking task, dual-motor task, dual-mental task, and combined motor and mental task.ResultsDM1 and DM2 patients differed significantly in temporal and stride characteristics compared to HC. Main differences in DM1 were slower gait and shorter stride length, while both DM1 and DM2 patients had a higher degree of variation of the swing time during dual-task gait, a parameter that reflects posture and balance. Impact of the cognitive dual task on gait pattern changes was also observed. Visuospatial ability correlated with gait changes in DM1, while executive functions had stronger influence in DM2 (p<0.01). Both patient groups had leg muscle weakness.ConclusionGait pattern was impaired in both patient groups concerning temporal and stride characteristics. Dual-task walking paradigm may discover mild initial gait changes and could provide early identification of fall risks and predict possible falls in DM patients.



from #Audiology via ola Kala on Inoreader http://ift.tt/1VEywve
via IFTTT

Comparison of temporal and stride characteristics in myotonic dystrophies type 1 and 2 during dual-task walking

Publication date: February 2016
Source:Gait & Posture, Volume 44
Author(s): S. Radovanović, S. Perić, D. Savić-Pavićević, V. Dobričić, J. Pešović, V. Kostić, V. Rakočević-Stojanović
ObjectiveWe analyzed temporal and stride characteristics in patients with myotonic dystrophy type 1 (DM1) and type 2 (DM2) while performing dual mental and motor tasks, and investigated correlations between gait parameters and cognitive impairments.MethodDual-task walking was performed by 37 patients (20 DM1 and 17 DM2) and 48 healthy subjects divided into two groups, age- and gender-matched control group for DM1 (HC1) and age- and gender-matched control group for DM2 (HC2). The subjects performed a basic walking task, dual-motor task, dual-mental task, and combined motor and mental task.ResultsDM1 and DM2 patients differed significantly in temporal and stride characteristics compared to HC. Main differences in DM1 were slower gait and shorter stride length, while both DM1 and DM2 patients had a higher degree of variation of the swing time during dual-task gait, a parameter that reflects posture and balance. Impact of the cognitive dual task on gait pattern changes was also observed. Visuospatial ability correlated with gait changes in DM1, while executive functions had stronger influence in DM2 (p<0.01). Both patient groups had leg muscle weakness.ConclusionGait pattern was impaired in both patient groups concerning temporal and stride characteristics. Dual-task walking paradigm may discover mild initial gait changes and could provide early identification of fall risks and predict possible falls in DM patients.



from #Audiology via ola Kala on Inoreader http://ift.tt/1VEywve
via IFTTT

Comparison of temporal and stride characteristics in myotonic dystrophies type 1 and 2 during dual-task walking

Publication date: February 2016
Source:Gait & Posture, Volume 44
Author(s): S. Radovanović, S. Perić, D. Savić-Pavićević, V. Dobričić, J. Pešović, V. Kostić, V. Rakočević-Stojanović
ObjectiveWe analyzed temporal and stride characteristics in patients with myotonic dystrophy type 1 (DM1) and type 2 (DM2) while performing dual mental and motor tasks, and investigated correlations between gait parameters and cognitive impairments.MethodDual-task walking was performed by 37 patients (20 DM1 and 17 DM2) and 48 healthy subjects divided into two groups, age- and gender-matched control group for DM1 (HC1) and age- and gender-matched control group for DM2 (HC2). The subjects performed a basic walking task, dual-motor task, dual-mental task, and combined motor and mental task.ResultsDM1 and DM2 patients differed significantly in temporal and stride characteristics compared to HC. Main differences in DM1 were slower gait and shorter stride length, while both DM1 and DM2 patients had a higher degree of variation of the swing time during dual-task gait, a parameter that reflects posture and balance. Impact of the cognitive dual task on gait pattern changes was also observed. Visuospatial ability correlated with gait changes in DM1, while executive functions had stronger influence in DM2 (p<0.01). Both patient groups had leg muscle weakness.ConclusionGait pattern was impaired in both patient groups concerning temporal and stride characteristics. Dual-task walking paradigm may discover mild initial gait changes and could provide early identification of fall risks and predict possible falls in DM patients.



from #Audiology via xlomafota13 on Inoreader http://ift.tt/1VEywve
via IFTTT

The neuroscience of 'happy' and 'sad' jazz improvisation

Musical creativity is one of the most mysterious abilities of the human brain. A study scanning the brains of jazz musicians gives new insights.

from #Audiology via ola Kala on Inoreader http://ift.tt/1INVSNt
via IFTTT

The neuroscience of 'happy' and 'sad' jazz improvisation

Musical creativity is one of the most mysterious abilities of the human brain. A study scanning the brains of jazz musicians gives new insights.

from #Audiology via ola Kala on Inoreader http://ift.tt/1INVSNt
via IFTTT